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My new over/under piston gun

Posted: Fri Apr 17, 2009 10:30 pm
by roughboy
This is my latest project please leave comments likes/dislikes. The gun is all metal with some brass fittings. I choose PVC for the barrel because the inner is smooth. the whole length of the gun is 2feet 9inch and not that heavy, it's easy to carry around. This is by far the most powerful gun i've made :twisted: .

Posted: Fri Apr 17, 2009 10:43 pm
by MrCrowley
Looks quite nice, what pressure do you run it at? Get some damage pictures/videos up too, I wanna see this thing in action :)

How's the ball valve trigger? Looks like you hip-fire this cannon with the trigger being at about your hip or maybe slightly further back?

Any other specs you can think of, add them to your post. :P

Re: My new over/under piston gun

Posted: Fri Apr 17, 2009 10:49 pm
by jackssmirkingrevenge
roughboy wrote:This is my latest project please leave comments likes/dislikes.
I like it, but dislike the enormous pilot chamber volume.

Posted: Fri Apr 17, 2009 11:06 pm
by daniel323
love the all metal look

i weould think to make the barrel longer for better velocity but your probably going for more power at a shorter distance :wink:

i would love to see a video of it firing.

keep it up

Posted: Sat Apr 18, 2009 1:10 am
by Brian the brain
You don't need the extra T in the pilot area if you fill through the handle.Just make sure you remove the schrader valve-stem.

If you made your piston right, it will surely actuate ( via bv)through an empty schrader.

Copper and aluminium are very suited to be used as a barrel.

The pvc ballvalve breechloader is very nice, but I'd go high pressure with this one ( effectively a sawed-off) so out with the PVC, in with metal!

Posted: Sat Apr 18, 2009 3:34 am
by qwerty
What range and accuracy do you get also try it with a smaller bore barrel to fire ball bearings

Posted: Sat Apr 18, 2009 3:40 am
by AdiabaticManiak
Nice shotgun style cannon you´ve got there! I like how the chamber is mounted, and for some esthetically bonus points you could make yourself some kind of soft grip along the chamber.

A nice job done!

Posted: Sat Apr 18, 2009 3:53 am
by sniper hero
good work

you could make a pump action reload system
just cut out a square out of the pipe where now the ballvalve is
then slide a pipe over it and a pice of pipe over the chamber
connect those pipes and TADA!

Posted: Sat Apr 18, 2009 5:03 am
by SubsonicSpud
Nice gun, I like the layout. Definatly remove that tee in the pilot area, and as BTB said, stick on a copper barrel and crank up the pressure :twisted:

SubsonicSpud

Posted: Sun Apr 19, 2009 12:53 am
by Gaderelguitarist
Nice cannon!

Take off that extra T like everyone is saying though.

A pump action system would probably make this a lot more fun to shoot and they're not difficult to build.

Posted: Sun Apr 19, 2009 1:13 am
by jackssmirkingrevenge
Gaderelguitarist wrote:A pump action system would probably make this a lot more fun to shoot and they're not difficult to build.
If that were true there'd be a lot more of them around ;)

Posted: Sun Apr 19, 2009 6:51 am
by psycix
Nice gun indeed! I suggest you get a fridge compressor!
What pressure do you currently run it at?

Posted: Sun Apr 19, 2009 1:11 pm
by Gaderelguitarist
jackssmirkingrevenge wrote:
Gaderelguitarist wrote:A pump action system would probably make this a lot more fun to shoot and they're not difficult to build.
If that were true there'd be a lot more of them around ;)

Well I guess I better get off my rump and post the pump action I made so we can spread some of the knowledge. :D

Posted: Mon Apr 20, 2009 12:17 am
by jackssmirkingrevenge
Gaderelguitarist wrote:Well I guess I better get off my rump and post the pump action I made so we can spread some of the knowledge. :D
Come to think of it, with a bit on ingenuity it really isn't that hard. Here's a design I had come up with a couple of years ago, never built it though - it's full auto or bust!

Image

Posted: Mon Apr 20, 2009 11:17 am
by Gaderelguitarist
Thats the idea behind mine, though i incorporated a spring to reset the sleeve.

How would this design achieve full auto? :?